A characteristic of lead acid batteries is that sulfate crystals tend to adhere to, and build up on the battery plates as a result of battery discharge. The deposit of sulfate crystals on the battery plates tends to eventually choke the battery by interfering with or blocking the movement of the electrolytes necessary for generating electric current during discharge. Replacement of individual cells, and often the entire battery, has been and continues to be the most widely used treatment for severe cases of sulfate deposits. Another solution is the application of high currents to the battery (fast charging). However, such fast charging techniques have been known to warp the battery plates and further damage the battery.
In response to the foregoing sulfate deposit problems and the lack of a safe and effective method for reducing or removing sulfate build-up, U.S. Pat. No. 5,063,341, issued Nov. 5, 1991 to Carl E. Gali, discloses a circuit that generates a positive voltage pulse train comprised of a plurality of pulses having a substantially uniform pulse width, rise time and peak voltage. The application of such fast rise time, short duration pulses in a pulse train to a deteriorated, sulfated battery has been found to substantially remove sulfate deposits from the battery plates. In spite of the benefits provided by the Gali rejuvenator, improved sulfate deposit removal and circuit operation is desired.